The extraction of an appreciable field emission current at low applied electric field is technologically important to the vacuum microelectronic devices such as field emission displays. Although planar electron sources with large emission area typically have been fabricated from arrays of metal such as molybdenum or semiconductors such as silicon microtips, recently carbon-based materials such as carbon nanotubes, diamond, diamond-like carbon, etc., have been investigated as less expensive and simpler alternatives. Electron emissions at low electric fields have been observed from these carbon-based films, but a suitable emission current density still requires a relatively high electric field (about 1 V/μm). The use of such a high electric field presents several complications when attempting to incorporate these devices into the above-identified technologies.
As such, there remains a need in the art for a device capable of achieving an appreciable field emission current at low applied electric field.